MacBookPro(2006)/battery life

Hi Daryl,

How long has it been since you last recalibrated your battery ( KB)? Perhaps resetting the SMC ( KB) might go some way to resolving the weirdness as well. Are you experiencing any significant reduction in battery life? Given 'average' usage patterns, the consensus is that one should calibrate the battery once a month to maintain proper function.

Li-ion batteries generally have a shelf-life of 2-3 years, depending on usage patterns. This is somewhat independent of the number of charge cycles the battery has accumulated. The Lithium-based content in the battery oxidises spontaneously. The process is accelerated by increased temperature, such as that experienced during normal laptop operation. If you are experiencing sudden drop in battery life, and recalibrating the battery a couple of times and resetting the SMC doesn't seem to make a difference, then it very well might be time to replace it.

In terms of charge, a Li-ion battery is under the most stress when it's at 0 and 100% charge capacity. In my opinion, whether the computer is off or asleep, doesn't really matter. However, if storing your battery for an extended period of disuse, it's best to maintain its charge at 50-60%, and making sure the storage location is both dry and relatively cool.

Yang

Message was edited by: Yang

Seeing the details of the battery's condition will be helpful. Follow this sequence of actions:

1) Do "About this Mac..." from the Apple Menu
2) In the resulting window, click the "More Info..." button
3) You are now looking at the utility "System Profiler"
4) Select "Power" in the left-hand pane
5) From the resulting info in the main pane, copy the "Battery Information" section and paste it here, omitting any serial numbers.

Done on my MBP, that info looks like this:

Battery Information:

Model Information:
Serial Number: Sony-ASMB012-xxxxxxxxx
Manufacturer: Sony
Device name: ASMB012
Pack Lot Code: 0001
PCB Lot Code: 0000
Firmware Version: 0110
Hardware Revision: 0500
Cell Revision: 0303
Charge Information:
Charge remaining (mAh): 5284
Fully charged: Yes
Charging: No
Full charge capacity (mAh): 5357
Health Information:
Cycle count: 15
Condition: Good
Battery Installed: Yes
Amperage (mA): 0
Voltage (mV): 12444

This gives the best look at battery condition.

Those numbers look like a reasonable healthy battery. "Health" for a 15" MBP battery is the "full charge capacity" divided by the baseline capacity, assumed to be 5600, so yours is 89 percent. Even though you say you seldom use the battery, the number of cycles says it gets some use. The battery is definitely a "use it or lose it" item.

I try to run my battery down about once a week, and calibrate once/month.